1. Field of the Invention
The present invention relates to a configuration of an apparatus serving as a transaxle for a working vehicle equipped with a longitudinal engine, and relates to a working vehicle equipped with such an apparatus.
2. Related Art
An engine having a horizontal engine output shaft extended in the longitudinal (i.e., fore-and-aft) direction of a vehicle is referred to as a “longitudinal engine.” There is a well-known conventional working vehicle (e.g., a utility vehicle) equipped with a longitudinal engine and a transmission assembly including a hydrostatic transmission (hereinafter, “HST”) and a mechanical transmission (e.g., a gear transmission), as disclosed by JP 2007-22379 A. In this vehicle, the HST and the mechanical transmission are configured to transmit power from the longitudinal engine output shaft to a transmission output shaft (e.g., right and left differential output shafts) extended in the lateral direction of the vehicle and drivingly connected to an axle of a drive wheel. The mechanical transmission is arranged to have its transmission shafts extended parallel to the transmission output shaft (i.e., in the lateral direction of the vehicle), thereby being minimized in the longitudinal direction of the vehicle. The HST is disposed on one of right and left sides of the mechanical transmission so as to extend laterally from the mechanical transmission instead of extending rearward from the mechanical transmission, thereby improving the turning performance of the vehicle, and improving the protection of the HST.
The vehicle has some problems. First, the vehicle is wrongly balanced so as to spoil its stability in traveling because the heavy engine is disposed laterally eccentrically in the vehicle. Second, the vehicle has to increase its size and the number of its component parts because the engine is separated from the transmission assembly and needs its own fixture member and a space separated from the transmission assembly. Third, the working vehicle also has to increase its size, especially in the longitudinal direction, because it has several power take-off (hereinafter, “PTO”) shafts including a front wheel driving PTO shaft and a working device driving PTO shaft, the front wheel driving PTO shaft being offset laterally from the engine, while the working device driving PTO shaft being extended rearward from the transmission assembly. Fourth, the transmission assembly has to have a portion where plural PTO shafts are collected and supported, thereby reducing durability of component parts in the portion and tending to cause noise from the portion.